29mm BSD Thor - NSL 2008 Ed.

[AKPilot]

Has anyone completed and flown theirs yet?

 

[dlb]

Has anyone completed and flown theirs yet?

well I got 3 of them, all complete and all with over 5 flights, but one with aboput 20 flights, ranging from E to G motor. I also seen about 4 others.

 

[AKPilot]

Any pics?

I found what I needed. I was just wondering if people did theirs without fiberglassing them. I know that a couple of people here, like Pantherjon, glassed his, but I didn't want to go to that effort if I didn't have to.

Still though could be a good learning experience I guess . . .


Oh, am putting rail buttons on this one though. The rod whip potential on this one scares me.

 

[dlb]

Any pics?

I found what I needed. I was just wondering if people did theirs without fiberglassing them. I know that a couple of people here, like Pantherjon, glassed his, but I didn't want to go to that effort if I didn't have to.

Still though could be a good learning experience I guess . . .


Oh, am putting rail buttons on this one though. The rod whip potential on this one scares me.

2 of my 3 have Rail buttons ( no whip till a "G" is used)and no glassing on any of them.
I did make a extention with a AV bay so "H" motor can be used, but expect close to a mile up on "H" motors.

A few pic's for ya!

 

[blackjack2564]

Yep... did glass it, only took about 10 minutes to do, 2wraps 6oz. It really doesn't need it, but I wanted to show someone how easy it was, and my stuff gets more beat up from travel than flying.

Flown with altimeter.
G-64 1800ft
G-76 G [?] 2400ft
H-97 4200ft with a tracker !!!

Great little rocket, lots of fun to fly.

 

[dlb]

and I'll show off my new entry, with a picture of the BSD wall.
Center left in the picture, with other BSD favorites coming soon!
No, BSD is not dead, just sleeping!

 

[Luv2launch]

It's a sweet flying bird although I have only flown mine a couple times so far the biggest motor was an E23 and the smallest being an estes d12 and a d13 or maybe a d21 not sure which it was built sometime last summer and I never used it had it in my semroc aerodart and it burnt 2 igniters and never lit so I tossed it back into the range box until a couple weeks back and scrapped the grain and used a new igniter and it lit finally.I used the stock launch lug on mine.

 

[rocketgroupmike]

Are these kits still available?

 

[Pantherjon]

Are these kits still available?

None that I am aware of..Tho I do know there were a few folks who purchased multiple kits..

I got one(I HAD to as NSL '08 was basically in my 'neck of the woods') and have flown it a number of times..I was the 'someone' that Blackjack showed how easy it was to glass a rocket!..I have flown it on a G64 and 3 times on G76G's..Last flight was on the G64 in the single deploy mode and got a defective delay grain which made the delay like a MINUS 1 instead of a 4 second delay..Totally trashed my avbay and put a small break in the lower tube(would hate to see what that tube would have looked like it it wasn't glassed)..Here mine is standing next to my 3" Thor in it's old paint scheme..Will have to get a more current picture with it and the 3"er in its new paint scheme-which is pretty much the same now as the NSL Thor..It is a great flyer and makes that distinctive 'Thor whistle'!

And a short video of it going up on a G76G

 

[DM1975]

I would love to get my hands on one of these kits. Anyone know when BSD is coming back on line? I know the website is back up but didn't his hand get even worse now?

In the mean time anyone that has an extra kit, if you want to make some cash just let me know what you want for it.

anyways, nice looking rockets guys, and dlb, those pain jobs look awesome...

 

[ttabbal]

and I'll show off my new entry, with a picture of the BSD wall.
Center left in the picture, with other BSD favorites coming soon!
No, BSD is not dead, just sleeping!

Good to hear. I want a Thor. Though I think I want a 54mm version.

The small 29mm one might be fun too. I could use more F and G powered rockets.

 

[jdud]

Oh, am putting rail buttons on this one though. The rod whip potential on this one scares me.

I've launched mine about 5 times...love the Thor whistle. One of the flights suffered a rod whip and made for an interesting flight. So, rail buttons would be a good upgrade.

The last flight suffered from a late ejection charge which ripped the chute off (my fault for using a swivel clip) and the body tube buckled a little near the top of the engine mount. I've already cut mine down near the yellow/gold transition, reinforced the buckle with a coupler and plan to install a baffle/coupler at the cut for a zipperless design.

 

[Boda]

Oh, am putting rail buttons on this one though. The rod whip potential on this one scares me.

What are rail buttons? What's the deal with rail whip and what causes it. New to MPR.

Thanks

 

[blackjack2564]

Rod whip is caused by a couple of things. High thrust motors or heavy rocket on too small of a rod. This can cause the rod to bend in the opposite direction of thrust or weight. Then flex back quickly or "whip back" causing the rocket to fly off at a bit of an angle or arced flight.

Usually happens with rockets flying on smaller rods like 1/8 3/16 or 1/4 in.

Rails are square tubes with a slot in them. You put 2 small buttons on the rocket several inches apart. The rail buttons slide into the slot to guide it.
Rails are very hard to bend due to being square and are used alot when flying High performance small rockets or heavier larger ones. I'm sure someone will post a couple of pics for you

 

[AKPilot]

Rail buttons go in place of a launch lug on a rod. They're made to be used with a launch rail of some sort. Here's what they look like:
Rail Buttons

Rod whip is where a launch rod, because of it's flexibility, "moves" due to the forces on it, such as pressure from a launch. Instead of staying rigid, like a rail, rods tend to bend. Hence "rod whip".

The problem with rod whip should be obvious, but if the rod bends too much on lift off, the rocket may follow the path of the "whip" meaning it could go way off a normal course or whever the rod is aiming towards, as the rocket leaves it.

With a rail there's very minute, if any, flexibility - making it a very rigid platform for launch MPR/HPR.

 

[Boda]

Thanks for the info and apologize for sidetracking the thread! I've only launched my Aerotech twice, once with an E and once with an F. I hadn't heard of rod whip or launch buttons before so I thought I would ask more seasoned folks! When I go to a G, should I be concerned about my Mantis launch rod?

Thanks agin for the info!

 

[DM1975]

No need to apologize, I had completely forgotten about railbuttons.com till AKPilot posted the link, and I needed to place an order for some rail buttons tomorrow so thank you for the vicarious help.

 

[jdud]

My previously mentioned experience with rod whip was due to my own stupidity. I always have a problem with 1/4" lugs swelling with the humidity and not fitting onto a 1/4" rod. So, instead of reaming out the lugs or simply not launching my thor; I put it on my 3/16" rod. A low altitude, horizontal flight on a G71 is very interesting (not to mention extremely dangerous).

Wise People Learn by Other People's Mistakes, Fools by Their Own...don't be a fool like me.

 

[dlb]

My previously mentioned experience with rod whip was due to my own stupidity. I always have a problem with 1/4" lugs swelling with the humidity and not fitting onto a 1/4" rod. So, instead of reaming out the lugs or simply not launching my thor; I put it on my 3/16" rod. A low altitude, horizontal flight on a G71 is very interesting (not to mention extremely dangerous).

Wise People Learn by Other People's Mistakes, Fools by Their Own...don't be a fool like me.

OUCH
You'll all be glad to hear I to didn't like the whip I got on my American Thor,( not as bad as yours)
So at that exact moment I said Rail Buttons, and all kits will include Rail Buttons.

below is a threesome, my favorites

 

[jdud]

Don,

I really like that sky wolf - hope that shows up in various sizes in the future BSD line up.

I was so impressed by the NSL Thor that I built an upscale, 29mm Javelin using LOC 1.6" tubing and nose cone. I utilized some of the same building techniques - TTW 1/8" ply fins, epoxy fillets, etc. The only improvements made were a zipperless design and rail buttons. She's flown like a champ on any 29mm reload I've launched her with so far.

 

[AstronMike]

My previously mentioned experience with rod whip was due to my own stupidity.

Wise People Learn by Other People's Mistakes, Fools by Their Own...don't be a fool like me.

I had an interesting run in with rod whip at the last launch, which had pretty constant winds all day long.

Flew my midsize Concorde glider, thankfully only on an F motor this time. Used a 1/4" rod, even though I usually use a 1/2" on a glider this size. Even though it only weighs around a pound (pod and glider total) all that wing surface area sure puts pressure on the rod with that wind blowing.

At the moment the motor lit, the wind suddenly gusted stronger, and the glider sure got whacked by the launch rod pretty well, as I could plainly see it whipping badly after liftoff.

Concorde ended up having an arced barrel rolled boost, which is unusual for such a solid flyer, and when I recovered it, there was the telltale dent near the back of the wing, off to one side a bit, where the rod obviously struck it, causing the aforementioned off color boost.

Might have to end up going to a rail for stuff like this and larger. Still, that combination of factors was pretty much asking for it...

 

[Boda]

OK, one more time to hijack this thread since it has been mentioned more than once.

What does "zipperless design" mean???

 

[jj94]

OK, one more time to hijack this thread since it has been mentioned more than once.

What does "zipperless design" mean???

A method of deployment and recovery that greatly reduces the chance of a zipper.

 

[Boda]

A method of deployment and recovery that greatly reduces the chance of a zipper.

OK then, what's a zipper? I have a couple of thoughts, but don't know if those are possible for what I'm thinking.

 

[BsSmith]

OK then, what's a zipper? I have a couple of thoughts, but don't know if those are possible for what I'm thinking.

A zipper is what happens when the shock cord rips through the body tube during a high speed deployment.

 

[Boda]

Got it!

It's what I was thinking, just took a couple thoughts to see how it was possible. With that being said, how can it be preventable? At high speed any positioning of the shock cord/nylon tubing has the possibility of ripping through the tube.

What would be a simple zipperless design be?

Thanks for all the great help to a newbie!

 

[jj94]

Got it!

It's what I was thinking, just took a couple thoughts to see how it was possible. With that being said, how can it be preventable? At high speed any positioning of the shock cord/nylon tubing has the possibility of ripping through the tube.

What would be a simple zipperless design be?

Thanks for all the great help to a newbie!

Whoops. I posted before I could show an example. Sorry about that. I know that Info Central had a good article on that, but I can't access the site right now. I guess antizippers work because the lower section had more mass, therefore having more momentum, which aids in the shock cord ripping into the tube. But if theres a coupler and bulkhead on the lower section of the rocket, and the parachute is kept in the upper section, there's a decreased chance in having a zipper since it has lower momentum and mass.

 

[Pantherjon]

OK, one more time to hijack this thread since it has been mentioned more than once.

What does "zipperless design" mean???

It is a way to configure an attachment point on the rocket so that when it deploys the chute/streamer the shock cord will not damage/rip or 'zipper' the tube if the the deployment is either late or early and the rocket is clipping along at a pretty good speed...Try to say that sentence with one breath!..LOL..Here is how I have it rigged in my 3" Thor:

Coupler glued halfway into the top of the tube with a bulk head and eye bolt..

Hope this clears up the mysterious 'zipperless design'

 

[redsox15]

Is that still possible to do if the rocket does not come apart? I am building a rocket where I want to do the above design but the tube isn't long enough for me to cut. Can I just put that bulkhead piece with the eye hook in the tube in order to separate the ejection charge from the parachute?

Matt

 

[jdud]

Here is a link to the Info Central article I based my zipperless design upon. So far this design has worked great.

Is that still possible to do if the rocket does not come apart?

This sounds more like a baffle. The anti zipper design outlined at info central incorporates a baffle into the design. However, the rocket splits below the payload (parachute) section. Upon ejection, the nose/payload section continues forward and the bottom section pulls the shock cord and chute out. The bulk of the force from the change in direction is absorbed by the eyebolt in the baffle and not against the side of the body tube.